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51.
Ali Asghar Ghafarizadeh Mahdi Malmir Samira Naderi Noreini Tayebeh Faraji Zeynab Ebrahimi 《Andrologia》2021,53(1):e13891
Induction of oxidative stress during the sperm preparation process for assisted reproductive techniques (ART) in men can weaken sperm parameters. Vitamin E (VE) is considered a factor in boosting male fertility. This experimental study (in vitro) aimed to assess the impact of VE supplementation on sperm quality and lipid peroxidation during sperm sampling at different times. For this mention, semen samples were collected from 50 asthenoteratozoospermic men. Samples were divided into control and test groups for 2, 4 and 6 hr that the test group was incubated with VE (2 mM). In two groups, total motility, progressive motility and viability based on the WHO 2010 criteria were assessed. Moreover, malondialdehyde (MDA) levels were evaluated in each group. In the control group, total and progressive motility and sperm viability were decreased significantly after 2 hr; however, MDA levels were increased significantly after 6 hr. Also, in the test group, sperm parameters were increased significantly after 2 hr, and MDA levels were decreased significantly after 6 hr compared to the control group. In outcome, in vitro VE supplementation may protect spermatozoa from the adverse effect of oxidative stress during sperm preparation via preservation antioxidant processes in normal condition. 相似文献
52.
Infertility is a major health issue affecting over 48.5 million couples around the world, with the male factor accounting for about 50% of the cases. The conventional semen analysis recommended by the World Health Organization (WHO) is the cornerstone in the evaluation of male fertility status. It includes macroscopic and microscopic evaluation of the ejaculate, which reflects the production of spermatozoa in the testes, the patency of the duct system and the glandular secretory activity. Evaluation of seminal fructose, sperm vitality and leucocytes (Endtz test) are useful adjuncts to semen analysis that provide information on specific clinical conditions. Though several computer-assisted sperm analysis (CASA) systems have been developed, conventional methods for semen analysis are still widely accepted in clinical practice. This review summarises the conventional techniques used in routine semen analysis and their diagnostic value in clinical andrology. 相似文献
53.
Varicocele is one of the major causes of male infertility and has a negative impact on spermatogenesis. The conventional semen analysis does not reveal the underlying subcellular mechanisms associated with defects in spermatozoa. Proteomics and bioinformatics analysis can be used to identify the molecular aetiologies associated with poor semen quality in varicocele patients. Mitochondrial dysfunction has been identified as the main factor affecting normal physiological functions of spermatozoa. This article discusses the proteomic studies of spermatozoa and seminal plasma in varicocele patients. Proteomics can identify potential spermatozoa and seminal plasma biomarkers in varicocele-mediated male infertility. In future, these protein biomarkers can be useful in the development of noninvasive diagnostic and therapeutic strategies for varicocele patients. 相似文献
54.
Alice Rosi Pedro Mena Fabio Castello Daniele Del Rio 《International journal of food sciences and nutrition》2021,72(1):70-81
AbstractInformation on children’s diet including bioactive compounds is quite scarce. This observational study investigated the composition of the diet of children living in Parma (Italy; n?=?172, 8–10?years) using 3-day food records completed in winter and spring. Mean daily intakes of food groups, energy and nutrients were obtained using the national food database, while (poly)phenol contents were estimated from Phenol-Explorer or by specific literature searches. Food consumption, energy and nutrient intakes decreased in spring and were partially in line with national data. Adherence to the nutritional recommendations was not satisfied for the majority of nutrients. Main contributors to the phenolic intake were flavonoids (flavan-3-ols) and phenolic acids (hydroxycinnamic acids), while main dietary sources were fruit, chocolate-based products, vegetables, and tea & coffee (decaffeinated). This study provided the first comprehensive analysis of the nutritional composition of children’s diet. Future research should look at the health implications of dietary choices in children. 相似文献
55.
Efficacy of intracytoplasmic sperm injection using intentionally cryopreserved epididymal spermatozoa 总被引:1,自引:6,他引:1
Oates Robert D.; Lobel Susan M.; Harris Doria H.; Pang Samuel; Burgess Colleen M.; Carson Ronald S. 《Human reproduction (Oxford, England)》1996,11(1):133-138
Microsurgical epididymal sperm aspiration was a great advancein the therapy of patients with non-recon-structable, obstructiveazoospermia, most notably congenital bilateral absence of thevas deferens. Using conventional in-vitro fertilization, pregnancieswere rarely achieved because the rate of oocyte fertilizationwas extremely poor. However, the use of retrieved spermatozoain conjunction with intracytoplasmic sperm injection (ICSI)has dramatically increased the likelihood of embryo formation.Typically, sperm and oocyte harvesting are performed simultaneously.We have investigated whether frozen-thawed spermatozoa workas well as fresh spermatozoa. When we had concluded from ourown population of patients (groups I and II) that they did,we adopted a policy of aspirating spermatozoa, primarily cryopreservingthem and using them for ICSI at a later date. We found the fertilizationrates of this latter cohort of patients (group III) to be excellent(37% per oocyte), and the ongoing pregnancy rate is quite satisfactory(40 % per couple, 29% per cycle). We offer this approach asan alternative to the traditional scheme because it markedlyeases the burden of partner scheduling on both the couple andthe clinicians involved. In addition, assurance of the availabilityof male partner spermatozoa can be attained prior to beginningovulation induction. 相似文献
56.
Genetic sperm defects and consanguinity. 总被引:5,自引:0,他引:5
B Baccetti S Capitani G Collodel G Di Cairano L Gambera E Moretti P Piomboni 《Human reproduction (Oxford, England)》2001,16(7):1365-1371
BACKGROUND: The existence of a genetic component to human infertility has been suggested, although neither the specific abnormalities involved, nor their genetic mechanism of transmission, are currently defined. We have examined, by transmission electron microscopy (TEM), ejaculate from 1600 males with fertility problems. Among the subjects studied, we focused on a group of patients whose family histories revealed different degrees of consanguinity, in order to evaluate the relationship between consanguinity and particular sperm alterations. METHODS AND RESULTS: A total of 64 consanguineous individuals were identified. In this group, excluding two azoospermic patients, 17 patients (27%) were found to have well recognized genetic ultrastructural defects affecting their entire sperm population: eight subjects had spermatozoa with "stunted tails", four "detached tail" spermatozoa, two "Kartagener's syndrome", two "miniacrosome" and one "round headed" spermatozoa. Since these alterations affect the total sperm population and do not respond to medical treatment, they are suspected of having a genetic origin. The remaining group of 1506 non-consanguineous patients suffered from the same genetic defects in only 15 cases (<1%). CONCLUSIONS: From the data presented, it appears that some very peculiar and rare sperm defects may have a genetic basis since they occur more frequently in consanguineous patients, and are related to different degrees of consanguinity. Since the ejaculate of the remaining patients, both consanguineous and not, showed diverse types of ultrastructural sperm anomalies that did not affect the entire sperm population, they might represent pathologies lacking a genetic basis. 相似文献
57.
目的 了解临沂市改水效果及水源的卫生防护状况。方法 对临沂市改水前后水源的卫生防护状况进行了调查,并对自来水水质进行了监测。结果 与改水前比较,水源的卫生防护状况有很大改善;改水后水源水、出厂水、末梢水水质合格率分别为58.33%、67.80%、51.85%。均比改水前明显提高(P<0.05)。改水后水质的主要超标项目为浑浊度,游度余氯、菌落总数和大肠菌群。结论 改水质自来水水质及水源及的卫生防护状况明显改善,水质主要受生活性污染,应加强对水源的卫生防护。 相似文献
58.
目的 了解青藏线水源水质卫生状况,为施工部队水源选择、洁治消毒提供参考依据。方法 硬度使用EDTA-2Na进行滴定,其余指标使用88型检水检毒箱测定。结果施工沿线基本无现成可利用的水源,所调查22个水源中9个存在生物污染,3个水源氯化物或硫酸盐严重超标;5个水源总铁严重超标。结论 摸清了放工沿线水源水质卫生状况,为部队施工和以后执行任 务时选择水源、进行水质改善提供了科学依据。 相似文献
59.
Aanesen Arthur; Fried Gabriel; Andersson Eva; Gottlieb Claes 《Human reproduction (Oxford, England)》1995,10(7):1885-1890
The possible presence of -aminobutyric acid (GABA) specificbinding sites on human spermatozoa was investigated. Swim-uppreparations of human spermatozoa were incubated with radiolabelledGABA in the presence of unlabelled GABA, alternatively displacersof GABAA/B receptors and GABA transport proteins. The resultsindicate that GABA specific binding sites are present on thesurface of human spermatozoa, and that these binding sites possiblyindicate the presence of GABA transport proteins. Furthermore,GABA at different concentrations was added to swim-up preparationsof human spermatozoa. Possible effects of GABA on sperm motility,hyperactivation and acrosome reaction were explored. No significantdifferences were observed between treated groups and controlsconcerning motility parameters and hyperactivation. Incubationwith GABA did not cause any increase in spontaneous acrosomereaction. However, spermatozoa treated with the calcium ionophoreA-23187 showed a small but significantly increased ability toundergo the acrosome reaction following preincubation in 104M GABA (P < 0.05). 相似文献
60.
Byron Asimakopoulos Aggeliki Tiptiri-Kourpeti Chrysa Metallinou 《Reproductive Medicine and Biology》2021,20(3):361-367